A full circular bearing or track is a nice option for rotating Mothra arches, but kPower currently favors a simple compass-belay for Mothra; for RAD, KIS, and lowest-capital-cost. My personal bias is evident too, from my long varied industrial crane and rigging experience, where powerful belay is the natural work method all day long. Belay is the AWES arch rotation method available now.

Liftech Consultants reported quay-crane operations at 30 lifts per hour (2002). Each lift requires connecting, winching, and disconnecting; the same sequence holds for a Mothra compass-belay around anchor-circle points. If twelve anchor points on 1km dia. circle are assumed, and each leg of the arch counts as a separate belay, a ninety-degree "hot" direction adjustment will take ~12 minutes, far faster than normal prevailing winds change. Landed rotation relaunches in new directions after calm, and as a back-up to hot-belay. Note that arches easily tolerate 45 degree wind-shifts to either side, smoothly self-land if caught sideways. Also note that upwind-legs can pull downwind-legs upwind by rigging a cross-rope (saving on winch).

These belay time assumptions are reasonable up to single-km scale kite arch, but beyond that non-rotating kite "domes" are favored that will merely tilt downwind in bulk (faster). Even beyond that, a vast plane of tilting kixels can in principle attain planetary-scale, adjusting to many internal wind directions at once (fastest). There are no insurmountable scaling barriers here.

•  ~ Dave Santos   5Feb2014           Discuss at:  AirborneWindEnergy/conversations/messages/11339

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• Terms and aspects:  
  • quay :: a concrete, stone, or metal platform lying alongside or projecting into water for loading and unloading ships.
• Related links and concepts:  
  • Liftech on Crane Productivity
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